Even if you don’t know squat about the blues, you probably have at least a passing acquaintance with the work of Robert Johnson. For starters, he’s in the Rock and Roll Hall of Fame — inducted in the hall’s first-ever class in 1986 as an early influence — which makes sense, given that modern-day guitar gods Eric Clapton and Keith Richards both have been impressed with and shaped by Johnson’s work.

Robert Johnson, shown here in 1935, was just 27 hyears old when he died under mysterious circumstances. Photo courtesy Columbia/Legacy/Copyright Delta Haze Corporation.

Johnson’s “Cross Road Blues,” — also called “Crossroads” in more modern versions — has been covered by Cream, Clapton, Elmore James, Jimi Hendrix, The Allman Joys (yeah, those Allmans, but as very young musicians), Van Halen, Steve Miller Band, Lynyrd Skynyrd, Molly Hatchet and The Doors. It’s the blues song that’s launched a thousand careers. Think of it as the “Smoke on the Water” equivalent for aspiring blues-rock artists. Even Johnson’s contemporary, Texas Alexander, covered “Cross Road Blues” in 1949 — a fact blues collector John Tefteller finds interesting largely because Alexander was still thinking about a song from 1936 more than a dozen years on.

And then, there’s that whole legend thing, about Johnson selling his soul to the devil at, where else? The crossroads.

“If you had to pick one Robert Johnson and say it’s the ultimate Robert Johnson record, I’d have to say ‘Cross Road Blues’ would be it,” said Tefteller, who owns Tefteller’s World’s Rarest Records. “It has all the elements of a great blues record. It has the great back story as to what it supposedly was about. It has the connection to the possible selling of his soul to the devil, which was supposed to keep him immortal — which has worked.”

Johnson’s influence has stretched far and wide, as evidenced by today’s musicians, who pay him homage by covering his songs. But in Tefteller’s book, nothing compares to the original song performed by the original artist, and “Cross Road Blues” was uniquely Johnson’s.

“It’s just a fantastic record,” Tefteller said. “It has everything you want. It has great lyrics, great playing. Clapton is good; I’m not taking anything away from him. John Hammond does a good version of this, too, and Ry Cooder. But if you have to pick the one to take with you to the desert island, it would be Robert Johnson.”

Of course, that whole “original artist” thing gets a bit sticky when it comes to Robert Johnson. He was sort of the Led Zeppelin of his day. (It’s a bit ironic, come to think of it, since Zep lifted some of Johnson’s work for “The Lemon Song” on “Led Zeppelin 2.”)

Robert Johnson "Me And The Devil Blues"/ "Little Queen of Spades" 78 Vocalion 4108 (1938). Johnson's penultimate record is almost as rare as his last, "Love In Vain Blues", with an estimated 10 to 15 copies still around. This is a nice copy -- the surface noise indicative of this grade being insignificant compared to the vocals and phenomenal guitar work by the man who influenced multiple music genres and countless musicians. The labels still display a deep blue proving this record has been well-preserved all these years. Condition: VG 5. Sold for $8,652.50 in April 2006. Photo courtesy Heritage Auction Galleries.

“Robert Johnson was good at taking other people’s material and making it his own,” Tefteller said. “That’s not a bad thing, but people have to be really aware that a lot of those songs he did were not his and his alone. They’re taken from other people and other songs.”

Johnson’s “Walkin’ Blues,” which exists only as a test, was recorded by Son House and later Muddy Waters. “Travelling Riverside Blues” and “If I Had Possession Over Judgment Day” were recorded by Hambone Willie Newbern, Tefteller said.

“Little Queen of Spades” is a Peetie Wheatstraw song that he took and changed around,” Tefteller said. “And there’s a controversy on the song he did called, ‘I Believe I’ll Dust My Broom.’ There are people who insist he ripped that off from Elmore James. Well, the story is that Elmore hung around with Robert Johnson as a teen in the 1930s, and it was Elmore’s song, and Robert just took it and recorded it because Elmore was too young to do it.”

Johnson wasn’t the only blues artist of the day re-doing others’ songs. He just happened to be the best at it.

“Everything he did became uniquely associated with him. Unless you dig, you can’t really recall whose the original was,” Tefteller said. The CD “The Roots of Robert Johnson” features the original artists performing 14 tracks that Johnson had later reworked to his own songs.

And while Johnson’s work is incredible and memorable, Tefteller thinks if he was pitted against his contemporaries, such as Skip James or Charley Patton, Johnson wouldn’t necessarily win the king of the blues title outright.

“Johnson just happens to have the most publicity because the British rock and rollers chose his songs over the others in the 1960s,” Tefteller said.

Because Johnson is who he is, there’s a cachet in possessing his records, the sales of which sometimes can be found in Goldmine’s Market Watch countdowns, as was the case in fall 2010.

“There was a copy of ‘Me and the Devil Blues’ that sold on eBay for $12,000, which is ridiculously more than it’s sold for in the past,” Tefteller said, “In the past, it’s always been a $4,000 to $5,000 record.”

Robert Johnson's "Cross Roads Blues" is one of his best-known songs.

Given Johnson’s stature as a musician, all of his Vocalion records are valuable and collectible, Tefteller said. Only one pressing of ‘Cross Road Blues’ was made on the Vocalion label, the label that is best known, but you might have a chance to find one on a couple of different labels, which were put out at the same time, Tefteller said. For instance, Sears put out records on the Conquerer label, Montgomery Ward issued records on its store label, while the Perfect and Oriole labels were from McCrory’s Drug Stores, Tefteller said.

“The key with him is condition. ‘Cross Road Blues’ is one of the harder ones to get, but they do turn up. It’s a question of what shape it is in when it does turn up,” Tefteller said. “A pretty well-battered copy of ‘Crossroads’ is going to sell for several thousand dollars. If you get one that’s really clean, it’s going to be much more than that.”

Tefteller estimates roughly 15 copies of Johnson’s ‘Cross Road Blues’ exist on Vocalion, of which less than a quarter of the copies are clean.

“As if the Vocalions weren’t hard enough to locate; the other labels are really hard to find,” Tefteller said. “If you go to the other labels, the numbers will get a whole lot smaller and a whole lot quicker. I had a copy of ‘Cross Road Blues’ on Conquerer, and it was beat and it was cracked and I still sold it.”

Tefteller has a full collection of Johnson’s 78s, plus a few of his original shellac test recordings from the 1930s. However, he warns collectors to be wary of Robert Johnson pressings they may see featured at online auctions.

“You will see on eBay every once in awhile one marked as an original Robert Johnson test pressing, and all of them are not original tests,” Tefteller warned. “They wind up selling for stupid money from people who don’t realize what they’re bidding on.”

Since 1961, when the original Robert Johnson LP was put out by Columbia as a way of reissuing the music, vinyl 78s were made from the original metal masters in the Columbia vaults, because the music couldn’t be directly recorded from the master. The pressed 78s could then be used to transfer the songs to other formats. He warns collectors to be skeptical when paying a lot of money for vinyl Robert Johnson test pressings they see featured in online auctions.

“They’re not that rare and they’re not that valuable,” he said. “They’re not good investments. If you just want to have one of those songs, like phonograph songs, on a 78 pressing, yeah, buy one of those vinyl pressings. But don’t think you’re getting something original from the 1930s. You’re not.”

The vinyl pressings were done from the 1960s to the 1980s; the shellac 78s were made in the 1930s, he said. Any potential collector wondering about the pedigree of a Robert Johnson recording on eBay should always ask the seller for details, he said.